Refrigeration



A ril 21, 1936. w. R. HAINSWORTH REFRIGERATION Filed April 2'7, 1934 6Sheets-Sheet l INVENTOR. BY 74% d wfl/azt ATTORNEY.

April 21, 1936- w. R. HAINSWORTH 2,037,782

' REFRIGERATION Filed April 2'7, 1934 6 Sheets-Sheet 3 [DID] [HID] HIUIIIDIUII IIEIII] HIDE INVENTOR.

F, m Y Lgggg ATTORNEY.

April 21, 1936. w. R HNNSWORTH 2,037,782

REFRIGERATION Filed April 27, 1954 s Sheets-Sheet 2 I l W ATTORNEY.

April 21, 1936. w. R. HAINSWORTH REFRIGERATION Filed April 27, 1934 6Sheets-Sheet 4 INVENTOR.

Jaw/ar- ATTORNEY.

W. R. HAINSWORTH REFRIGERATI ON April 21, 1936.

6 Sheets-Sheet 5 Filed April 27, 1934 DUDE DUDE! DUI] I. INVEI VTOR.

waw

ATTORNEY.

6 Sheets-Sheet 6 T A' A' W. R. HAINSWORTH REFRIGERATION- Filed, April27, 1934 April 21, 1936.

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Patented Apr. 21, 1936 UNITED STATES PATENT OFFICE REFRIGERATIONApplication April 27,

24 Claims.

My invention relates to refrigeration and more particularly to aircooled refrigerators of the absorption type.

It is an object of my invention to provide effective natural draftcooling for the heat rejecting portions of an absorption typerefrigerator. Another object is to provide an absorption typerefrigerator having a condenser disposed at a high level and adequatelycooled by natural draft. A further object is toprovide an absorptiontype refrigerator having a condenser disposed at a high level below thetop of the cabinet and adequately cooled by natural draft.

A still further object is to provide adequate cooling for a condenserand an absorber of an absorption type refrigerator in which thecondenser is directly cooled and the absorber is indirectly cooled byair.

My invention is particularly applicable to ab sorption refrigerationapparatus generally of the nature of that disclosed in Patent No.1,609,334 to Von Platen et al. and more specifically in accordance withthe disclosure in an application of A. R. Thomas, Serial No. 673,815,and is, in 55 general, characterized by exposure of the heat emittingparts of. the apparatus to atmospheric air. and acceleration of naturalair flow with respect to such parts by maintenance of a column ofrelatively warm air in the path of flow of air beyond the heat emittingparts. This ap-- plication relates back for common subject matter to myapplication, Serial No. 663,486.

The nature of my invention together with the objects and advantagesthereof will be more fully understood from consideration of thefollowing description in connection with the accompanying drawings, ofwhich Fig. 1 is an expanded or schematic View of a refrigerationapparatus contemplated by my invention;

Fig. 2 shows a refrigerator comprising a cabinet, shown in verticalsection, with the top of the cabinet elevated, and the refrigerationapparatus of Fig. 1 assembled as a unit and partly withdrawn from thecabinet;

Fig. 3 is a rear view of the refrigerator cabinet with the top andapparatus unit in place;

Fig. 4 is a detail section on line 4-4 of Fig. 3;

Fig. 5 is a rear perspective view of the refrigerator cabinet; and

Fig. 6 is a detail section like Fig. 4 and illustrating a furtherembodiment of my invention.

Referring to Fig. 1 of the drawings, the refrigeration apparatusillustrated includes a generator 10, a condenser H, an evaporator orcooling 1934, Serial No. 722,640

element l2, and an absorber l3. The generator Ill has a substantiallyhorizontal portion divided by a partition into what may be referred toas a weak liquid chamber l4 and a strong liquid chamber iii. Astand-pipe l6 communicates at its lower end with the weak liquid chamberl4, and a thermosyphon conduit [1 is provided, opening into the strongliquid chamber l5 and connected to the upper end of the stand pipe 16,as known in the art. The generator may be heated by any suitable meansas, for instance, a gas burner, not shown, arranged so that the flame isdirected into the' flue l8 which extends through the horizontal portionof the genera tor. The weak liquid chamber M of the generator isconnected through conduit l9, a liquid heat exchanger 26, and conduit 2|to the upper part of the absorber l3. The bottom of the latter isconnected through conduit 22, the liquid heat exchanger 20, and conduit23 to an analyzer comprising a vessel 24. The lower part of the analyzeris connected through conduit 25 to the strong liquid chamber I5 of thegenerator.

The upper part of the generator stand pipe I6 is connected throughconduit 26 to the analyzer 24, the opening of conduit 26 in the analyzerbeing in the lower part thereof and below the normal liquid leveltherein for the purpose hereinafter described. The upper part of theanalyzer 24 is connected by a conduit 21 to the upper end of the lowercondenser loop 28, the lower end of this loop being connected to theupper part of a vessel or jacket 29 around the upper end' of conduit 21.The latter is advantageously provided with a plurality of heat radiationfins 30 between the analyzer 24 and the vessel 29. The upper part ofvessel 29 is connected by conduit 3| to the upper end of the condensercoil 32, the lower end of which is connected by conduit 33 to the upperend of the evaporator l2. The lower part of vessel 29 is connected byconduit 34 to an intermediate part of the evaporator.

The upper end of the evaporator I2 is connected by conduit 35, a gasheat exchanger 36, and conduit 31 to the lower part of the absorber 13.The upper part of the latter is connected by conduit 38, gas heatexchanger 36, and conduit 39 to the lower end of the evaporator I2.

The condenser II is vented to the absorber l3 through a conduit 40connected from conduit 33 to the lower part of the absorber. In conduit40 is connected what may be termed a pressure vessel 4|.

The absorber I3 is provided with a cooling coil 42 connected by conduits43 and 44 to a condenser 45. The absorber cooling coil 42, conduits 43and 44, and condenser 45 form a secondary heat transfer system which ischarged with a suitable heat transfer fluid such as methyl chloride.Both condensers H and 45 are provided with heat radiation fins for aircooling as hereinafter described. Conduit 2| is also advantageouslyprovided with heat radiation fins, as shown, for air cooling of liquidflowing through this conduit to the absorber.

The above described apparatus is charged with an inert gas as, forinstance, hydrogen at a predetermined pressure, and a solution ofrefrigerant in a liquid absorbent, such as a water solution of ammonia.The pressure at which the hydrogen is introducedinto the apparatuscorresponds to the pressure at which ammonia condenses to liquid at apredetermined temperature, which is preferably a high room temperature.

The operation of this system is fully described in said applicationSerial No. 673,815 of A. R. Thomas, and is briefly as follows:

Ammonia vapor, expelled by heat from solution in the generator l6, flowsthrough conduit 26 into the analyzer 24, where it bubbles upward- 1ythrough strong solution in the lower part thereof. From the upper partof the analyzer, the ammonia flows through conduit 21 to the firstcondenser loop 28. The finned portion 36 of conduit 21 comprises whatmay be termed a high temperature rectifier and the jacket 29, whichreceives condensate from the condenser loop 28, forms a low temperaturerectifier. In these rectifiers, water condenses out of the ammonia vaporand drains back into the analyzer 24, as known in the art. Liquidammonia, formed in the condenser loop 28, overfiows from vessel 29through conduit 34 into the lower part of the evaporator l2. the upperpart of vessel 29 through conduit 3| tothe further condenser coil 32.From the latter, liquid ammonia drains through conduit 33 into the upperpart of the evaporator l2. The purpose of this arrangement is tomaintain a constant temperature in the refrigerator with variations inroom temperature and may be fully understood from consideration of thedescription in said Thomas application Serial No. 673,815.

In the evaporator or cooling element 2, the liquid ammonia evaporates bydiffusion into the hydrogen which enters the evaporator through conduit39. The resulting gas mixture flows from the evaporator through conduit35, gas heat exchanger 35, and conduit 31, into the lower part of theabsorber l3. In the latter, ammonia is absorbed out of the gas mixtureinto weak solution which enters the absorber through conduit 2|. Theweak gas returns from the upper part of the absorber to the evaporatorthrough conduit 38, gas heat exchanger 36, and-conduit 39. The weaksolution flows to the absorber from chamber M of the generator throughconduit l9, liquid heat exchanger 26, and conduit 2|. Enrichedabsorption solution accumulates in the lower part of the absorber l3,from where it flows through conduit '22, liquid heat exchanger 20, andconduit 23 into the analyzer 24-, where it stands substantially at thesame level as in the absorber. 'From the analyzer, the strong solutionflows through conduit 25 into chamber l5 of the generator, from where itis raised through conduit I! by thermosyphon action into the upper partof the stand pipe l6, as known in the art.

Uncondensed ammonia vapor flows from Referring to Figs. 2 and 3, thereis illustrated a refrigerator comprising a cabinet 46 provided with arefrigeration apparatus unit 47, which latter comprises the systemdescribed in connec tion with Fig. 1. The parts of the apparatus are thesame in all views and accordingly indicated by-the same referencenumerals. In Fig.2, the refrigerator cabinet is shown in verticalsection with the top elevated, and the refrigeration apparatus unit isshown in side elevation, substantially withdrawn from the cabinet. InFig. 3,

. the refrigerator is shown in rear view with the apparatus unitassembled in the cabinet.

The refrigerator cabinet 46 comprises a thermally insulated storagecompartment 48 accessible by means of an insulated door 49 and providedwith an aperture 56 in the rear'wall. Below the storage compartment 48there is an apparatus compartment 5|, and the side walls 52 of the'cabinet. 46 are extended rearwardly of the storage compartment 48,forming a chamber 53 which extends upwardlyfrom the rear of theapparatus compartment 5| to the top of the refrigerator cabinet. Thelatter is open both at the ,bottom and at the rear. The aperture 50opens from the storage compartment 48 into the upper part of the rearapparatus chamber 53. In this refrigerator cabinet there issubstantially no limitation of air circulation outside of the storagecompartment 48, that is, the apparatus compartment comprising the lowerchamber 5| and rear chamber 53, is, for all intents and purposes.exposed to the atmosphere. j

The refrigeration apparatus is mountedon a frame comprising a pair ofvertical angle irons 54 connected by cross-bars 55 and, between theirlower ends, a sheet metal shelf 56. The latter is formed with integralbrackets 51 at each end which are bolted or otherwise secured to thelower ends of the angle iron's 54. The bottom shelf 56 supports a unitcomprising the generator l6, analyzer 24, and liquid heat exchang- Thisunit is surrounded by thermal insulating material, such as mineral wool,and provided with a light casing 58 of suitable material such as lightgauge sheet metal. The front end of the generator flue |8 extendsthrough the casing 58, as may be seen in Fig. 2, for proper location ofa heating element, such as a gas burner and its associated controls, notshown. As shown in Fig. 3, the other end of the genera- .tor flue |8 isprovided with a plug 59. accessible from without the casing 58 forfacilitating insertion of a suitable flue cleaning device when desired.connected to an extension 60,-a1s0 shown in Fig. 3, which terminates atthe top of the refrigerator cabinet, the opening 16 in the top of thecabinet being visible in the rear perspective view in Fig. 5. Thegenerator fiue extension 60 is provided with a suitable dilution device6| having openings, not visible in the drawings, in the bottom of aflared portion 62 to allow flow of air into the flue, which results incooling and dilution of the flue gases before discharge at the top'ofthe refrigerator, as known in the art.

To the upper part of the angle iron frame are secured a pair of spacedplates 63, 64, which may be referred to as side plates. Between theangle irons 54, and of a height corresponding substantially to theheight of the side plates 63, 64, is

mounted a thin sheet of metal 65 which may be referred to as a backplate. The ammonia condenser H and the secondary or methyl chloridecondenser 45 are arranged one above the other This end of the generatorflue is also ondary or absorber cooling condenser 45 is a partitionplate 66, secured at each end to the side plates 63, 64.

The conduit 21 connecting the analyzer with the lower coil 28 of theammonia condenser I I extends through the lower part of the space 67formed between the condensers II, 45,- and the back plate 65. Thisportion of conduit 2! is pro- ,vided with the heat radiation fins 3D andhas a slight slope toward the analyzer and constitutes, as previouslyset forth, an air cooled or high temperature rectifier.

The arrangement of condensers and rectifier, which is of primaryimportance in this invention,

- will be more clearly apparent from a consideration of the detailsection shown in Fig. 4. Referring to this figure, it is seen that thespace 67 constitutes a flue, closed on three sides by the side plates63, 64 and the back plate 65. The other side of the flue GT is formed bythe condensers I I, .45 and the bafile plate 56. The bottom of the fiueis closed by the high temperature rectifier portion of conduit 21. Thetop of the flue is open, and unobstructed flow of air from the flue isprovided by openings 68 in the top 69 of the refrigerator cabinet. Theseopenings may also be observed in the rear perspective view of thecabinet shown in Fig. 5. It will now be understood that substantiallyall of the air which enters the flue space 6! must pass through thecondensers' II, or the rectifier portion of conduit 21. As indicated bythe arrows in Fig. 4, air entering the fiue space 6! flows between thecondenser coils and between the condenser heat radiation fins andbetween the rectifier fins 30. The spacing ofthese radiation fins may bemade small enough so that substantially all of the air fiowingtherebetween must pass in thermal contact therewith. This arrangementmakes possible air cooling of the heat radiation portions of therefrigeration unit ata high efiiciency without the use of a fan or othermeans for producing a forced draft, for not only is there secured goodthermal transfer from the condensers and rectifier to the air, but thereis also obtained a greater flow of air for the reason that no unheatedair enters the flue space 61, and the column of air in this space is ata much higher temperature and therefore of much less weight than anequivalent column of air at the room temperature. In short, thisimprovement brought about by my invention is characterized by theprevention of dilution of air in the flue by the entrance of unheatedair. It will be understood that the high temperature rectifier may beotherwise located and the bottom of the flue completely closed, as byanother plate 30a shown in Fig. 6, or the lower end of condenser may belocated next to the back plate 65 to close the bottom of the flue space.

which may be referred to as a window closure. The latter is located andconstructed so that it fits within and closesthe aperture or windowopening 50 in the rear of the refrigerator storage compartme'nt 48 whenthe refrigeration. apparatus unit is mounted in position in the cabinetas hereinafter described. The evaporator I2 is mounted on the front ofthe window closure Ill through which extend the connections from theevaporator to the other parts of the apparatus, as previously described.The gas heat exchanger 36 i, located between the angle irons 54 of theunit frame, wherefore the back plate 65 is provided with a shallowrecess ll, shown in Fig. 3, and r channel or recess 12 is provided inthe insulation of the rear wall of the refrigerator storage compartment&8 below the window 50, as shown in Fig. 2, to' receive the gas heatexchanger when the refrigeration apparatus unit is mounted in thecabinet. The recess 1| in the back plate 65 may be lined with thermalinsulation so a major portion of the gas heat exchanger will be wellinsulated when the unit is in the cabinet.

In Fig. 5, there is shown a rear perspective view of the refrigeratorcabinet provided with a rear cover plate I3 for the purpose ofpresenting an aesthetic appearance from the rear without secrificingflow of air over the heat emitting poi tions' of the refrigerationapparatus unit when the latter is mounted in place. upper part of thecover plate I3 is formed an open grille or screen M. An opening lfi'isprovided in the lower 1 part of the rear cover plate I3 for access tothe generator plug 59. The rear cover plate 53 whicl be referred togenerally as a screen, is low. ily removable from the cabinet. To thisend, the side edges of the screen are flanged inwardly and provided witha plurality of slots I'l, each having an enlarged lower portion forming,in appearanceyan inverted keyhole, as may be seen in the small cut awayportion in Fig. 5. Along the rear edges of the cabinet wall is providedcorresponding plurality of slightly protruding s u-ws I8, as may be seenin Figs. 2 and 3. To asmmoc the screen, it is placed against the rear ofthe cabinet so that the heads of the projecting screws 18 pass throughthe enlarged lower portions of the slots H, and then lowered so that thescrews become recessed in the narrow upper portions of the slots,whereby the screen is retained in place, the upper portions of the slotsbeing narrower'than the diameter of the heads of the screws 18. It willbe understood that if it is desired to tighten the screws I8 afterassembly of the screen, it will be necessary to provide openings for a..screw driver in the screen opposite the slots II.

Referring to Figs. 2 and 5, assume that the screen I3 and the top 69 areremoved from the refrigerator cabinet t6. The refrigeration unit M maynow be placed in the position shown in Fig. 2 and moved toward thecabinet l6, until the back plate 65 and angle irons 5 t abut the rearwall of the storage compartment 18 The unit is then secured in thisposition by any suitable means, not shown, as screws, bolts providedwith wing nuts, or the like. In this position the evaporator IE iswithin the upper part of the refrigerator storage compartment 58, theclosure member It fills the window opening or aperture '50, the upperpart of the gas heat exchanger 36 is recessed in the channel 72, thehorizontal portion of the generator and liquidv heat exchanger unit iswithin the lower chamber- 5B of the apparatus To this end. the

flue 1 compart'ment, and the other parts of the apparatus are within thenarrow rear chamber 53 of the apparatus compartment. The back plate 65lies against the wall of the storage compartment 48, and it will beunderstood that this plate may be omitted as far as its function ofclosing the flue 61 is concerned. The screen 13 is next assembled on therear of the cabinet, as previouslydescribed, and the top 69 lowered intoplace, thus completing the refrigerator assembly. For the purpose ofreplacement or repair, the cabinet and apparatus unit are disassembledin the reverse order from that of assembly just described.

Experience with refrigerators constructed as above described hasdisclosed the relation between the depth of the flue space 61, that is,the distance of the condenser H from the back plate 65, and thetemperature differential of the condenser and the air. In the instanceof a condenser provided with six heat radiation fines per inch andhaving a constant heat input of 300 calories per hour. changing the fluedepth from one inch to two inches results in a decrease in temperaturedifferential from 40 F. to 325 R, which is a decrease of 7.5" F. Uponfurther increasing the depth of the flue from two inches to threeinches, the temperature differential decreased from 325 F. to 27" F.,which is a decrease of 5.5 F. Further increase in the depth of the flueto four inches results in a decrease in temperature differential to 25"F., which is a decrease of only 2 F. Therefore, taking intoconsideration the conservation of cabinet space, it has been determinedthat the optimum flue depth or condenser spacing is three inches. It hasalso been determined that tilting the condenser by bringing the lowerend thereof nearer to the back plate 65 does not appreciably affectthe'results, wherefore, to allow as much space as possible at the backof the cabinet for flow of air to the condenser, it has been foundadvantageous'to tilt the condenser inwardly at the lower end with theupper end spaced the optimum distance of three inches from the backplate or cabinet wall, forming a flue having a maximum depth at the topof three inches. It has also been determined that the optimum spacing ofthe condenser radiation fins is obtained with approximately four finsper inch.

It will be obvious to those skilled in the art that various changes maybe made in the construction and arrangement without departing from thespirit of the invention, and therefore the invention is not limited towhat is shown in the drawings and described in the specification butonly as indicated in the following claims.

I claim:

1. In a refrigerator, a cabinet having a thermally insulated storagecompartment and an ap-.

paratus compartment, said apparatus compartment having a portion open toatmosphere at the top and rear of said cabinet, absorption typercfrigeration apparatus including a'cooling element in said storagecompartment, a condenser comprising a flat pipe-coil in the upper partof said portion of the apparatus compartment and in a substantiallyvertical plane adjacent the open rear of said apparatus compartment andhaving closely spaced heat transfer fins substantially perpendicular tosaid plane, an absorber, means for cooling said absorber including asecond condenser similar to said first condenser and located below thelatter substantially in said plane thereof, imperforate wall membersforming the other sides of a flue of which one side is form'edby saidcondensers, means to prevent flow of air into said flue intermediatesaid condensers, a generator, at rectifier for vapor from said generatorcomprising a substantially horizontal conduit having closely spacedtransverse heat transfer fins and located in a manner to encounter, inthermal transfer relation, all air entering the bottom of said flue, anda closure member for the rear of said cabinet including a grilleopposite said condensers.

denser, and a closure member for the open side of said cabinet includinga grille opposite said condenser.

3. Refrigeration apparatus of the absorption type including a condensercomprising a flat pipecoil in a substantially vertical plane and havingclosely spaced heat transfer fins substantially perpendicular to saidplane, and means including said condenser and substantially imperforatemembers completely bounding, except at the top,

a flue space at one side of said condenser.

4. Absorption type refrigeration apparatus includir; a condensercomprising a relatively flat pipe-coil in a substantially upright planeand having heat transfer fins substantially perpendicular to said plane,an absorber, a cooling system for said absorber including a secondcondenser similar to said first condenser and located substantially insaid plane thereof, imperforate wall members forming the other sides ofa flue of which one side is formed by said condensers, means to preventflow of air into said flue intermediate said condensers, a generator, arectifier for vapor from said generator comprising a substantiallyhorizontal conduit having transverse heat transfer fins and located in amanner to encounter, in

thermal exchange relation, all air entering the bottom of said flue.

5. Absorption type refrigeration apparatus in- 'cluding a condenserdisposed in a substantially upright plane and having extensive heattransfer surfaces substantially perpendicular to said plane,

an absorber, means for cooling said absorber ineluding a secondcondenser similar to said first condenser and. located substantially insaid plane thereof, means completely bounding, except at the top, a fluespace of which .one side is formed by said-condensers, and means toprevent flow of air into said flue intermediate said condensers.

6. A condenser for absorption type refrigeration apparatus disposed in asubstantially upright plane and having extensive heat transfer surfacessubstantially perpendicular to said plane, and means including saidcondenser completely bounding, except at the top, a flue space at oneside of said condenser, whereby all air entering said flue space mustpass in-thermal exchange relation with said condenser.

'7. A condenser for absorption type refrigeration apparatus disposed ina substantially upright plane and constructed and arranged for coolingby flow of air in contact therewith and substantially perpendicular tosaid plane, and.means including said condenser completely bounding,except at the top, a flue space at one side of said condenser, wherebyall air entering said flue space must pass in thermal exchange relationwith said condenser.

8. In a refrigerator, a cabinet having an apparatus compartment open toatmosphere at the top and one side of the cabinet, absorption typerefrigeration apparatus including a condenser disposed in asubstantially upright plane in said compartment adjacent said open sideand constructed and arranged for cooling by flow of air in contacttherewith and substantially perpendicular to said plane, and meansincluding said condenser and substantially imperfor'ate memberscompletely bounding, except at the top, a flue space at the side of thecondenser opposite said open side of the cabinet.

9. In a refrigerator, a cabinet having an apparatus compartment open, toatmosphere at the top and one side of the cabinet, absorption typerefrigeration apparatus including a condenser disposed in a subsantially upright plane in said compartment adjacent said open side andconstructed and arranged forcooling by flow of air in contact therewithand substantially perpendicular to said plane, means including saidcondenser and substantially imperforate members completely bounding,except at the top, a flue space of which a portion toward said open sideof the cabinet is bounded by said condenser,'and a closure member forthe open side of said cabinet including a grille opposite saidcondenser.

10. Refrigeration apparatus of the absorption type including a heat.rejecting portion disposed in a substantially upright plane, andconstructed and arranged for cooling by flow of air in contact therewithand substantially perpendicular to said plane, and means includingsubstantially imperforate members and said heat rejection portioncompletely bounding, except at the top, a flue space at one side of saidheat rejecting portion.

11. In a refrigerator, a cabinet having an apparatus compartment open toatmosphere at the top and one side of said cabinet, absorption typerefrigeration apparatus having a heat rejecting portion disposed inasubstantially upright plane adjacent the open side of said compartmentand constructed .and arranged for cooling by flow of air in contacttherewith and substantially perpendicular to said plane; and meansincluding substantially imperforate members and said heat rejectionportion completely bounding, except at the top, a flue space at one sideof said heat rejecting portion opposite said open side of the cabinet.

12. Refrigeration apparatus of the absorption type having a plurality ofheat rejecting portions,

one of which is disposed in a substantially upright plane and all ofwhich are constructed and arranged for cooling -by flow of airin contacttherewith and substantially perpendicular thereto, and means includingsaid heat rejecting portions completely enclosing. except at the top,' aflue space, whereby all air entering said flue must pass in thermalexchangev relation with a heat rejecting portion.

13. In a refrigerator, a cabinet, absorption type refrigerationapparatus including a condenser adapted for cooling by air andhorizontally spaced from an exterior wall portion of said cabinet,andmeans including said wall portion and said condenser for completelyenclosing a flue open only at the top, whereby all air entering saidflue must pass in thermal exchange relation with said condenser.

14. In a refrigerator, a cabinet, and absorption type refrigerationapparatus removable as a unit from said cabinet and including an aircooled condenser disposed in a substantially upright plane so that whensaid apparatus is assembled with said cabinet there is formed a fluespace between said condenser and an outer wall of said cabinet, andmeans including said condenser for completely enclosing said flue spaceexcept at the top, whereby all air entering said flue space must pass inthermal exchange relation with said condenser.

15. Refrigeration apparatus of the absorption type including an aircooled condenser disposed in a substantially upright plane and havingone side exposed to the atmosphere, and means including said condenserfor completely enclosing, except at the top, a space on the other sideof said condenser to form a flue into which air may flow only in thermalexchange relation with said condenser.

16. In a refrigerator, a cabinet having a thermally insulated storagecompartment and an apparatus compartment, said apparatus compartmenthaving a portion open to atmosphere at the top and rear of said cabinet,absorption type refrigeration apparatus including a cooling element insaid storage compartment, an air cooled conentering the bottom of saidflue.

17. In an absorption type refrigerator, a cabinet having a verticalinsulating wall, a condenser exposed to atmospheric air and spaced fromsaid wall to form a space, said space receiving air through saidcondenser and constituting a flue, and means for excluding unheated airfrom said flue. I

18. In an absorption type refrigerator, a cabinetjiaving a verticalinsulating wall, a condenser spaced from said wall, members includingsaid condenser and wall forming a substantially vertical flue at oneside of and coextensive in height with said condenser and completelyclosed except at the side formed by the condenser and at the top.

19. In a refrigeration apparatus of the absorption type, aflrstcondenser, a generator connected to supply refrigerant vapor tosaid condenser, an

absorber, means for cooling said absorber including a second condenser,said condensers being disposed one above the other, and members formingwith said condensers a natural draft flue substantially coextensive inheight with said condensers. I

20. In an absorption type refrigerator, a cabinet having an uprightinsulating wall, a condenser spaced from said wall a distance ofapproximately three inches and means including said wall and saidcondenser forming a natural draft flue substantially coextensive inheight with said condenser and completely closed exceptat the sideformed by the condenser and at the top.

21. In an absorption type refrigerator, an upright wall, a firstcondenser, a generatorcoiinected to supply refrigerant vapor to saidcondenser, an absorber, means for cooling said absorber including asecond condenser, said condensers being disposed one above the other andspaced from said wall a distance of approximately three inches, andmembers forming with said condensers and said wall a natural draft fluesubstantially coextensive in height with said condensers.

22. In an absorption type refrigerator, an upright wall, a firstcondenser comprising a flat pipe coil having approximately fourtransverse heat transfer fins per inch, an absorber, means for coolingsaid absorber including a second condenser similar to said firstcondenser, sai'cl condensers being disposed one above the othersubstantially in the same plane and spaced from said wall, and membersforming with said wall and condensers a natural draft flue substantiallycoextensive in height with said condensers, the space between saidcondensers and said wall being a maximum of approximately three inchesat the top of said flue.

23. -In an absorption type refrigerator, an upright wall, a condensercomprising a flat pipe coil having transverse heat radiation fins andhorizontally spaced from said wall in a plane inclined downwardly towardsaid wall, and members forming with said condenser and said wall anatural draft fiue substantially coextensive in height with saidcondenser.

- 24. In a refrigerator, a cabinet having a vertical wall, a condenserformed of pipe disposed in substantially a vertical plane and spacedfrom said vertical wall a distance appreciably greater than the diameterof said pipe, members substantially closing certain sides of the spacebetween the condenser and vertical wall against flow oi unheated airtherethrough while allowing flow of air through the condenser to form anatural draft flue open at the top and receiving air through thecondenser, said condenser as a whole being constructed and arranged toallow a wide horizontal free :area of air flow upwardly through theflue, and apparatus connected to said condenser i'or forming arefrigerant circuit.

" WILLIAM R. HAINSWORTH.

